planet fitness pants are the skin tight, almost see through latex pants worn by overweight women that work out at planet fitness. these women of course have no business wearing anything that revealing/tight in public but because they're working out (or just came for the free pizza) they feel the urge to show off their flabby, cottage cheese bodies like they are supermodels

damn man, check out the planet fitness pants over there! watching this lady's jelly rolls do cardio is soothing like watching waves crash on the beach.